Ocular Anatomy Flashcards
1
Q
What are the 7 layers of the eyelid?
A
- Skin
- Subcutaneous Areolar
- Orbicularis
- Submuscular Areolar
- Orbital Seption
- Posterior Muscular
- Tarsal Plate
- Palpebral Conjunctiva
2
Q
What is telecanthus?
A
Abnormally increased distance b/n the medial canthi of the lids
3
Q
Trichiasis is secondary to what?
A
Entropion
4
Q
What is Phthiriasis palpebrarum is caused by?
A
infections of lashes caused by phthirus pubis
5
Q
The skin layer contains what 3 things?
A
- Fine hairs
- Sweat glands
- Sebaceous glands
6
Q
Where is the thinnest skin layer of the body?
A
Eyelid
7
Q
T/F the skin layer of the eyelid contains fat?
A
False
8
Q
What kind of CT is found in the subcutaneous and submuscular areolar layer?
A
Loose CT
9
Q
What structure can be found in the subcutaneous layer of the eyelid?
A
Levator aponeurosis
10
Q
What structure does the orbicularis layer of the eyelid contain?
A
Palpebral portion of the orbicularis oculi
11
Q
What nerve innervates the Orbicularis Oculi?
A
CN7
12
Q
What is the orbital portion of the Orbicularis Oculi in charge of?
A
Forced blinks
13
Q
What is the palpebral portion of the Orbicularis Oculi in charge of?
A
Spontaneous and reflex blinking
14
Q
What are the two portions of the palpebral portion of the Orbicularis Oculi?
A
- Muscle of Riolan (pars ciliaris)
2. Muscle of Horner (pars lacrimalis)
15
Q
The muscle of Horner is in charge of?
A
Tears: encircles canaliculi to help drain tears
16
Q
The muscle of Riolan is in charge of?
A
Roll: rotating lashes
Tide: keeps it tight
Divide: gray line
17
Q
Paralysis of the orbicularis will eventually result in a condition known as..?
A
Ectropion: lower lid droops away from globe
18
Q
What structures does the submuscular areolar layer contain?
A
Upper: Levator aponeurosis
Palpebral potion of the main lacrimal gland
Upper and Lower: Peripheral and Marginal arcades
19
Q
What are four pertinent negatives that you should have for orbital cellitus?
A
- Fever
- Decreased Vision
- EOM restriction
- Pain
20
Q
What kind of CT is the orbital septum?
A
Dense Irregular CT
21
Q
What are the function(s) of the orbital septum
A
- Barrier to the orbit in the upper and lower lids
- Prevents fat from falling down onto lid margins
- Keeps infection localized to anterior portion of the eyelid, away from the orbit
22
Q
What meds would you give for Orbital Cellulitis?
NOTE: polymicrobial (staph & strep)
A
- Augmentin: cell wall synthesis inhibitor
- Cephalexin: cell wall synthesis inhibitor
- Azithromycin: 50S subunit
- Doxycycline: 30S
- Fluroquinolones: DNA synthesis inhibitor
23
Q
What becomes the orbital septum?
A
Peri-orbita: loosely covers orbital bones
24
Q
What is the orbital septum continuous with?
A
Periorbita and periosteum of skull
25
What attaches to the orbital septum medially
Posterior Lacrimal Crest
26
Does the orbital septum protect the lacrimal sac from infection?
Yes - Located posterior
27
What layer is the insertion site of the levator aponeurosis?
Superior Orbital Septum
28
What structures are in the posterior muscular layer?
1. Superior levator Palpebrae
| 2. Muller's muscles (superior and inferior)
29
Superior Levator Palpebrae originates from where?
Lesser wing sphenoid
30
What is the function of the Superior Levator Palpebrae?
Main retractor of upper lid
31
What is Whitnal's ligament?
Fulcrum of the Superior Levator Palpebrae that allows muscle to change course from anterior posterior to superior inferior
32
What is the Levator aponeurosis?
Fanned shaped tendon of Superior Levator Palpebrae that attaches to skin and anterior surface
33
What does the levator aponeurosis attach to (3 places)
1. Skin
2. Orbicularis/Subcutan
3. Tarsal plate
34
Where is the attachment of the levator aponeurosis to the skin of upper lid form?
Superior palpebral furrow
35
Where does the lateral horn of the levator aponeurosis attach to?
Whitnal ligament
36
Where does the medial horn of the levator aponeurosis attach to?
medial palpebral ligament
37
How is the inferior palpebral furrow formed?
Indirect attachment of the inferior rectus muscle into skin
38
What does the eyelid furrows separate?
Tarsal and orbital portions of lid
39
Muscle of Muller is what kind of muscle?
Smooth Muscle
40
Muscle of Muller has what kind of receptors and is innervated by what?
A2
Sympathetic nervous system
41
Where does the inferior tarsal muscle originate from?
Fascial sheath of inferior rectus
42
Horner's syndrome is a DEC in which innervation?
Sympathetic
43
What is happening when the lid is retracted back too much
1. Too much sympathetic (overaction of mueller)
| 2. Thyroid issue
44
When you hear Thyroid eye disease, what should you think?
Fibroblast proliferation
45
What is a normal Interpalpebral fissure distance?
10-12
46
Tarsal plate is made of what kind of connective tissue
Dense irregular
47
Tarsal plate structure
Horizontal and vertical collagen fibrils that surround meibomian glands
48
What kind of glands are meibomian glands?
Sebaceous
49
What layer are meibomian glands located in?
Tarsal
50
How many meibomian glands on top and bottom lids?
25 and 20 respectively
51
Upper and lower tarsal plates combine to form
Medial and lateral palpebral ligaments
52
The medial palpbral ligament attaches to where?
Maxillary Bone
53
Lateral palebral ligament attaches to where?
Whitnall's ligament
54
What kind of gland/secretions are meibomian and Zeiss?
Sebaceous and Holocrine
55
Zeiss gland function?
Lubricates lashes
56
What kind of gland is Gland of Moll?
Apocrine
57
What layer and macrophages, PNMs to protect from infection
Palpebral conjunctiva
58
What are the layers of the palpebral conjunctiva?
1. Epithelial layer
| 2. Stroma
59
Is the epithelial layer of the palpebral conj stratified?
Yes
60
Goblet cells found in where?
Palpebral conj mostly inferior nasal fornix
61
Stroma layer of the palpebral conj is what kind of CT?
Loose vascularized CT
62
Two layers of the stroma layer of palpebral conj?
1. Superficial lymphoid layer
| 2. Deep fibrous layer
63
Stroma of Palpebral Conj aka
1. Submucosa
| 2. Substantia propria
64
The Superficial lymphoid layer of Stroma of Palebral Conj contains
IgA Macrophages, mast cells, PMNs and eosinophils (immunologically active)
65
The deep fibrous layer of Stroma of Palebral Conj function
Connects the conj to underlying internal structures continuous with tarsal plate
66
What does the deep fibrous layer of Stroma of Palebral Conj contain?
1. Accessory lacrimal glands
| 2. Wolfring and Krause
67
Internal hordeolums are infections of what gland?
Meibomian
68
External hordeolums are infections of what gland?
Zeiss
69
What kind of gland is the gland of Moll?
Aprocrine and Sweat
70
Krause and Wolfring gland is what kind of gland
Accessory lacrimal and merocrine
71
Wolfring gland is found where?
Tarsal conj
Deep fibrous layer of stroma of palpe conj
72
What are the Holocrine glands of the eye?
Meibomian and Zeiss
73
What are the Apocrine glands of the eye?
Moll and Goblet
74
What are the Merocrine glands of the eye?
Lacrimal, krause, wolfring
75
What branch of 7 innervates the orbicularis oculi for voluntary motor
Zygomatic branch of the facial nerve
76
What branches innervate the upper eyelids for sensory?
1. Supraorbital and supratrochlear branches of the frontal branch of V1
2. Lacrimal branch of V1
77
What are the direct branches of V1
1. Nasociliary
2. Frontal
3. Lacrimal
78
What branches innervate the lower eyelids for sensory?
1. Medial: infratrochlear branch of nasociliary branch of V1
2. Zygomaticalfacial of Zygomatic of V2
3. Infraorbtial of V2
79
What supplies blood to the deep eyelid structures?
Palpebral arcades
80
Palpebral arcades are formed by the union of the?
medial palpebral artery and the lateral palpebral artery
81
Medial palpebral artery is a branch of the?
ophthalmic artery
82
The lateral palpebral artery is a branch of the?
lacrimal artery
83
What provides blood the the bulbar conj and ciliary body?
Anterior ciliary arteries
| why pt's with uveitis get circumlimbal injections and decrease aq humor production
84
What provides blood to the superficial areas of the lid?
Facial artery of the external carotid
85
Veins of the lid run _____ to arteries
Parallel
86
Where do the veins of the lids drain into?
palpebral and ophthalmic veins
87
Lateral lymphatics of the conj drain into
Parotid lymph nodes
88
Medial lymphatics of the conj drain into
Submandibular lymph nodes
89
What are the infections that cause Preauricular lymphadenopathy
Viral Conj (Herpes, EKC)
Chlamydia
Dacryoadenitis
Gonorhea (only bacteria that does)
Parinaud's oculoglandular Syndrome
90
Parinauds oculoglandular sydrome presents with what?
Significant Preauricular and Submandibular Lymphadenopathy
91
What causes follicles on conj?
CHAT
1. Chlamydia
2. Herpes
3. Adenovirus
4. Toxic (Brominidine)
92
The corrugator muscle function:
Medial depressor, runs obliquely
Pulls the corner of the eyebrows down and in
Occurs during concentration
93
The Procerus muscle function:
Medial depressor on bridge of nose
Pulls the skin b/n eyebrows straight down
Flares nose- Anything to do with nose
94
What divides the lacrimal gland into two portions?
Levator Aponeurosis
95
Lacrimal gland is what kind of gland
Exocrine gland with merocrine secretion
96
What branches of what artery supplies the lacrimal gland
Glandular branches of the lacrimal artery
97
What drains the lacrimal gland
Lacrimal vein
98
What part of the orbit contains the only lymphatic vessels
Lacrimal gland
99
Where does the lacrimal gland receive its innervation? What kind of innervation is ti?
Parasympathetic: Lacrimal nerve of the pterygopalatine (sphenopalitine) ganglion of CN VII
100
Reasons for Epiphora?
1. Ectropion
2. Overproduction of tears
3. Underdrainage
101
Overproduction of tears can be caused by what?
1. Allergy
2. Dry eye syndrome
3. Corneal irritation
102
Underdrainage of tears is cause by what?
1. NLDO
103
Nasal Lacrimal Duct Obstruction in old people is caused by what?
1 reason is AGE (related to stenosis or involutional stenosis)
Another reason: Maxillary Sinus Infection
104
Nasal Lacrimal Duct Obstruction in Young people is caused by what?
Valve of Hasner' issues
105
What is the number one reason for canaliculitis (bacteria)?
Actinomyces israelii
106
Causes of Acute Dacryoadenitis (pathogen)?
1. Staph (#1 cause)
2. Sarcoidosis
3. Mononucleosis (EBV)
107
What is responsible for keeping the puncta open?
Lacrimal Papilla (CT)
NOTE: NOTE: The lacrimal papilla is the small rise in the bottom eyelid just before it ends at the corner of the eye closest to the nose. In the middle of it is the lacrimal punctum, a small hole that lets tears drain into the inside of the nose through the lacrimal canaliculi.
108
How long are canalicular
(2+8=10 mm)
109
Structure of Drainage System?
Vertical 2 mm
Horizontal 8 mm
Common Canaliculi
Lacrimal system
NLD
Hasner
110
What prevents backflow from lac sac?
Angle of Common Canaliculi
111
What muscle surrounds the Canalilculi to assist in tear drainage?
Muscle of Horner
112
Where does the Lacrimal Sac lie within?
Fossa of medial orbit wall, formed by post lacrimal crest of lacrimal bone and ant lacrimal crest of maxillary bone
113
How long is lac sac?
10-12 mm
114
What cells are in the lacrimal sac?
1. Double epithelium (superficial columnar and deep basal)
2. Goblet cells
3. Microvilli
115
What ligament straddles the lacrimal sac?
Medial palpebral ligament
116
What divides the lacrimal sac into upper and lower section?
Muscle of Horner
117
What is Dacryocystitis cause by?
1. Infection of lacrimal sac caused by NLDO
118
What makes of the Medial wall of the Orbit?
SMEL
Sphenoid (body)
Maxilla
Ethmoid
Lacrimal
**(thinnest and smallest wall of orbit)**
